A major side effect of the hypertransfusion treatment for Thalassemia major is accumulation of iron in body tissues, and the primary cause of death for these patients is iron deposition in the heart. The conventional treatment for iron overload consists of daily subcutaneous deferoximine administration. This study will test the hypothesis that intravenous high-dose desferoximine over prolonged exposure time can increase the urinary iron excretion, resulting in the lowering of serum ferritin levels in these patients.